1. Field of the Invention
An improved exercise machine simulative of cross-country skiing is provided by the invention.
2. Background Information
Ski treadmills, exercise machines that allow a user to simulate the motions involved in cross-country skiing, have been popular for many years. Perhaps the best known machines of this sort are made by the NordicTrack Corporation of Chaska, Minn. Examples of the variety of machines made by that firm, or for apparent use with their equipment, can be found in the patent art and include:
U.S. Pat. No. 5,533,952, to Shaber, who uses a handgrip with multiple anchor points in order to vary the muscles being exercised. PA1 U.S. Pat. No. 5,387,168, to Bostic, describes adding a waist belt to a NordicTrack ski treadmill. PA1 U.S. Pat. No. 4,728,102, to Pauls, shows a load indicator used with this sort of apparatus. PA1 U.S. Des. Pat. Nos. 351,435 and 335,908 show two cosmetic designs for a ski treadmill. PA1 U.S. Pat. No. 5,762,584 shows an electrically controlled variable resistance load for a skiing simulator. PA1 U.S. Pat. No. 5,595,556, to Dalebout et al., which shows a treadmill having pivoting handles. The apparatus provides nearly constant resistance to both hand and foot motions regardless of whether the hand or foot is moving forwardly or rearwardly. PA1 U.S. Pat. No. 5,203,751, to Chang, which shows a cross-country skiing simulator providing arm and leg resistance in both forward and rearward direction. PA1 Haalheim, in U.S. Pat. Nos. 4,618,139 and 4,529,194, shows cross-country skiing treadmills providing arm exercise in both directions of motion. The machine shown in U.S. Pat. No. 4,618,139 has poles pivotally mounted to the base. The machine shown in U.S. Pat. No. 4,529,194 does not appear to be collapsible for storage, because of the tracks along which the pole carriages slide. Moreover, if some sort of lubrication were used on the pole carriage tracks, it would be likely to rub off the tracks onto the user's clothing.
Other art in the area includes: